Rorie D K
Am J Physiol. 1982 Nov;243(5):H732-7. doi: 10.1152/ajpheart.1982.243.5.H732.
The importance of endothelial cells in the removal of norepinephrine from synaptic clefts in dog pulmonary artery was studied. Strips of artery cut helically were denuded of endothelium by gently stroking the intimal surface with a wooden applicator stick or were studied with endothelium intact. All strips were prelabeled in L-[3H]norepinephrine (2 X 10(-7) M) and mounted for superfusion. Superfusate was collected continuously before, during, and after electrical stimulation (10 V, 2 ms, 2 Hz). Measurements were made of the amounts of [3H]norepinephrine and its metabolites in superfusate and in tissue. These studies have established that 3,4-dihydroxyphenylglycol is of neuronal origin and O-methylated metabolites are of extraneuronal origin. The formation of extraneuronal metabolites in smooth muscle and endothelium was examined by either blocking uptake of norepinephrine into each, in turn, or by combining blockade of uptakes with the elimination of access of norepinephrine to endothelial tissue by completely removing it. Electrical stimulation elicited the overflow of large amounts of norepinephrine, 3,4-dihydroxyphenylglycol, and O-methylated metabolites into superfusate in strips with intact endothelium; in strips denuded of endothelium there were striking decreases in the amounts of O-methylated metabolites produced. These studies show that pulmonary arterial endothelium participates in the extraneuronal metabolism of norepinephrine released by sympathetic nerve stimulation.
研究了内皮细胞在犬肺动脉突触间隙去甲肾上腺素清除中的重要性。用木质涂抹棒轻轻擦拭内膜表面，将螺旋状切割的动脉条去除内皮，或保留完整内皮进行研究。所有条带均预先用L-[3H]去甲肾上腺素（2×10(-7)M）标记，并安装用于灌流。在电刺激（10V，2ms，2Hz）之前、期间和之后连续收集灌流液。测量灌流液和组织中[3H]去甲肾上腺素及其代谢产物的量。这些研究表明，3,4-二羟基苯乙二醇起源于神经元，O-甲基化代谢产物起源于神经元外。通过依次阻断去甲肾上腺素进入平滑肌和内皮的摄取，或通过将摄取阻断与完全去除内皮组织使去甲肾上腺素无法进入相结合，来检查平滑肌和内皮中神经元外代谢产物的形成。电刺激导致完整内皮条带中大量去甲肾上腺素、3,4-二羟基苯乙二醇和O-甲基化代谢产物溢入灌流液；在去除内皮的条带中，产生的O-甲基化代谢产物量显著减少。这些研究表明，肺动脉内皮参与交感神经刺激释放的去甲肾上腺素的神经元外代谢。
